[alsa-devel] [usb-audio] VIA/Audinst HUD-mx2: One of two PCM device is available for playback
Hi,
This sound card has two PCM devices. If the sound card is realized "card 0", there are "hw:0,0" and "hw:0,1". But former seems not to generate sound and latter seems to generate.
This issue is reported to Ubuntu-jp and LinuxMint forum. The reporter said this happens in Fedora18 so I think this does not depends on these desktop invironment. https://forums.ubuntulinux.jp/viewtopic.php?pid=98940#p98940 http://forums.linuxmint.com/viewtopic.php?f=49&t=128478
Please see attached lsusb.log to know usb information and alsainfo.sh in detail.
Audinst HUD-mx2 applies VIA Technologies chip internally. http://www.audinst.com/en/bbs/board.php?bo_table=HUDmx2&wr_id=4
The sound card has a lamp which turn on when data comes. When "hw:0,0" is used, the lamp turns on but no sound. When "hw:0,1" is used, the lamp turns on and sound.
My question is: 1. does hw:0,0 seem to be available when some control are changed? 2. are there some ways to use hw:0,1 as a default?
Regards
Takashi Sakamoto o-takashi@sakamocchi.jp
Takashi Sakamoto wrote:
This sound card has two PCM devices. If the sound card is realized "card 0", there are "hw:0,0" and "hw:0,1". But former seems not to generate sound and latter seems to generate.
This device has multiple alternate settings for PCM and AC-3 playback. The driver creates multiple devices for those because it has no other mechanism to distinguish them.
The AC-3 setting happens to be listed first in the descriptors.
- are there some ways to use hw:0,1 as a default?
Entires like these in ~/.asoundrc or /etc/asound.conf:
defaults.pcm.card 0 defaults.pcm.device 1
I'd guess the driver could be changed to enumerate alternate settings in two steps, first for PCM formats, then for others.
Regards, Clemens
Thanks Clemens,
This device has multiple alternate settings for PCM and AC-3 playback. The driver creates multiple devices for those because it has no other mechanism to distinguish them.
I want to ask further question about this.
Can we realize whether the PCM device for AC-3 stream (hw:0,0) works or not from the output of lsusb? The sound card has several outputs (headphone, line, S/PDIF) and I don't know only hw:0,1 connects to all of them or not.
Entires like these in ~/.asoundrc or /etc/asound.conf:
defaults.pcm.card 0 defaults.pcm.device 1
But the device is connected by USB. The card ID differs depending on the user's system. If the other sound card is identified as "card 0", this setting is applied to it, not to the target device.
Can we write additional information to identify this sound card in these line?
I'd guess the driver could be changed to enumerate alternate settings in two steps, first for PCM formats, then for others.
This is a better solution. But I have a little knowledgement about USB Audio Class and it's implementation to ALSA.
Regards
Takashi Sakamoto
(Jun 04 2013 20:22), Clemens Ladisch wrote:
Takashi Sakamoto wrote:
This sound card has two PCM devices. If the sound card is realized "card 0", there are "hw:0,0" and "hw:0,1". But former seems not to generate sound and latter seems to generate.
This device has multiple alternate settings for PCM and AC-3 playback. The driver creates multiple devices for those because it has no other mechanism to distinguish them.
The AC-3 setting happens to be listed first in the descriptors.
- are there some ways to use hw:0,1 as a default?
Entires like these in ~/.asoundrc or /etc/asound.conf:
defaults.pcm.card 0 defaults.pcm.device 1
I'd guess the driver could be changed to enumerate alternate settings in two steps, first for PCM formats, then for others.
Regards, Clemens
Takashi Sakamoto wrote:
This device has multiple alternate settings for PCM and AC-3 playback. The driver creates multiple devices for those because it has no other mechanism to distinguish them.
Can we realize whether the PCM device for AC-3 stream (hw:0,0) works or not from the output of lsusb?
If the device declares that it supports AC-3, it'd assume that this will work (if the data actually is AC-3).
defaults.pcm.card 0 defaults.pcm.device 1
The card ID differs depending on the user's system.
defaults.pcm.card "HUDmx2"
Regards, Clemens
participants (2)
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Clemens Ladisch -
Takashi Sakamoto